Programmatically create html tags

generate_html.js

function _create_html(inner_html, attributes = {}, data_attr = {}, self_closing = false, tag = null) {
	let html = '<' + tag
	if (!is_array(inner_html) && is_object(inner_html)) {
		attributes = inner_html
		inner_html = null
	}
	for (let key in attributes) {
		html = html + ' ' + key + '="' + attributes[key] + '"'
	}
	for (let key in data_attr) {
		html = html + ' data-' + key + '="' + data_attr[key] + '"'
	}
	if (self_closing && !inner_html) {
		html = ' />'
	}
	else {
		html = html + '>'
		if (inner_html) {
			if (inner_html.constructor === Array) {
				for (let elem of inner_html) {
					html = html + elem
				}
			}
			else {
				html = html + inner_html
			}
		}
		html = html + '</' + tag + '>'
	}
	return html
}

function tag(tag, inner_html = null, attributes = {}, data_attr = {}, self_closing = false) {
	return _create_html(inner_html, attributes, data_attr, self_closing, tag)
}

function tag_factory(tag) {
	return function (inner_html, attributes = {}, data_attr = {}, self_closing = false) {
		return _create_html(inner_html, attributes, data_attr, self_closing, tag)
	}
}

function is_array(val) {
	return val instanceof Array
}

function is_object(val) {
	if (val === null) {
		return false
	}
	return ((typeof val === 'function') || (typeof val === 'object'));
}

output.js

let th = tag_factory('th')
console.log(create_tag('thead', create_tag('tr', [th('hello'), th('hola', {class: 'big_text'}), th('hi')]), {class: 'hide'}))
// outputs
// <thead class="hide"><tr><th>hello</th><th class="big_text">hola</th><th>hi</th></tr></thead>